Swimming practice apparatus



Oct. 29, 1935. E. HESS SWIMMING PRACTICE APPARATUS 3 Sheets-Sheet 1Filed Feb. 10, 1835 lnveniozw: 27 ErFzy-wd Hess, 6 ra nn-w Oct. 29,1935. E. HESS SWIMMING PRACTICE APPARATUS Filed Feb. 10, 1933 3Sheets-Sheet 2 Ina/anion. Erhc; z dfss, 7 diffs Oct. 29, 1935. E. HESS2,019,224.

SWIMMING PRACT I CE APPARATUS Filed Feb. 10, 1933 3 Sheets-Sheet 3fave-77,2?) r.- .E'rhard Hes-s Patented Oct. 29, 1935 UNITED STTSClaims.

This invention relates to machines for instruction in the practice ofswimming, being intended more particularly, though not exclusively, forinstruction in what is known as the crawl (or 51 "sometimes the Americancrawl) stroke in which the hands of the swimmer pass each through asubstantially vertical orbit at the side of the body. In this movementthe hands are extended forward in alternation, sweeping downwardly andback- 'Iwardly, the feet being kicked up or down in alternation andcoordinately with the movement of the hands and arms.

In this machine provision is preferably made so that not only are themovements of the hands and feet guided and coordinated to conform to thecorrect execution of the stroke so that the swimmer learns by practiceinstinctively to perform such movements, but the mechanism is operatedby the muscular power of the swimmer himself so as to develop and trainthe muscles which primarily come into play in executing this stroke;

The invention will be best understood by reference to the followingdescription when taken in connection with the accompanying illustrationof one specific embodiment thereof, while its scope will be moreparticularly pointed out in the appended claims.

In the drawings:-

Fig. 1 is a side elevation of a machine embody- 20 ing one form of theinvention;

Fig. 2 is a plan view of the machine shown in Fig. 1;

Fig. 3 is a plan of the driving connections between one of the handstraps and the driven sprocket" on a somewhat enlarged scale;

Fig. 4 is a cross-sectional elevation on the line 4-4 in Fig. 3;

Fig. 5 is a rear elevation of the machine shown in Figs. 1 and 2;

Fig. 6 is a side elevation of one form of load imposing deviceassociated with the intermediate driven sprocket wheel; and

Fig. 7 is a partial end elevation of the parts shown in Fig. 6 on anenlarged scale and looking in the direction of the arrow in Fig. 6.

Referring to the drawings and to the embodiment of the invention thereshown for the purpose of illustration, the apparatus is mounted upon alight but strong portable frame, preferably consisting of angle irons,and comprising primarily a. pair of spaced, upright members I! and I3connected at their bottom ends by the member l5 and somewhat below theirupper ends by the horizontal member I! forming one side 55.; (herein theleft-hand side) of the frame. Associated with this are correspondingupright members I9 and 2!, with a similar lower connecting member and anupper connecting member 23, forming the opposite or right-hand side ofthe fram'e, leaving an intervening space in which 5 the subject,hereinafter referred to as the swimmer, is positioned.

The bottom connecting members are prolonged at their rear to provide, inconjunction with uprights 25 and Zl and cross-connecting members 10 29,3! and 33, a smaller extension of the frame for supporting certain ofthe operating parts at the rear thereof. At the front the opposite sidesof the frame are connected at the bottom by the cross-connecting member35. 35

Fixedly secured to upright frame members 36 and between the two sides ofthe frame is a body rest or table 31 adapted to support the body of theswimmer and on which he lies prone and face downward, his legs extendingrearwardly over 20 the two separate leg boards 39, the latter beinghinged to the rear edge of the body rest or table 3! so as to be freelymovable up and down with relation thereto and provided each at its rearend with a foot rest or holder M adapted to re- 25- ceive the toes ofthe swimmer and hold the feet and legs in fixed position on the leg'boards, so that movements imparted to the latter are adapted to directthe movements of the swimmers legs. extending through the slot 33 in theleg board so as to be adjustable for persons of different leg lengths.

Each leg board has journaled on its under side a cam roll 45 riding onits own cam M, the two cams being secured to a common cam shaft 59journaled in bearings supported by the rearwardly extending and upwardlyinclined frame ment bers 5|. The two cams M are set apart and arepreferably designed to provide a uniform 4O rising and falling movementfor the leg boards. To guide the swimmers hands and arms in the properorbit there is provided at each side of the frame and rigidly secured threto a closed, guiding trackway 53 of the shape best shown in Fig. 1, 45where it will be seen that it comprises an upper, substantiallyhorizontal portion merging into a lower portion which conforms to thearc of a circle. The trackways thus present guides Which define in eachcase a non-circular orbit lying in a substantially vertical plane ateach side of the swimmer. This trackway herein consists of a continuous,relatively thin strip of metal but of generally rectangularcross-section, there being 55 Each foot holder M is fastened by a bolt30 two similar guiding trackways, one for the right arm and another forthe left arm.

Mounted to run easily and with slight friction on the trackway is asmall, light guide frame comprising the grooved rollers 55, 55 (Fig. 3)engaging the opposite convex edges of the tracking strip, the rollersbeing journaled in the plate 5'! which holds them in fixed relation tothe trackway but is pivotally secured to the sliding connecting rod 59through which the machine is driven by the movement of the swimmersarms. The arm propelling mechanism for the two opposite sides of themachine is substantially the same and one only need be described. 7

Means are provided to permit the swimmer to grasp and simultaneouslymove the two connecting rods 59, and for this purpose there is attachedto each rod a holding strap 6| adapted to encircle and be fastened aboutthe palm of the hand, allowing the hands to remain open in executing thearm stroke. Each strap has a swivel attachment to its connecting rod bymeans of a bolt secured in a threaded hole in the connecting rod, aspaced series of holes being provided so that the position of the strapmay be adjusted to suit the reach of the individual.

The forward and downward movement of the swimmers hand acts through theconnecting rod 59 to rotate a shaft 63 journaled in bearings on theframemember I! (the right-hand shaft being journaled on the frame member 23),the axis of this shaft being aligned in close approximation to theshoulder of the swimmer about which the sweep or full movement of thearm takes place and coinciding substantially with the center of the arcto which the lower run of the guiding trackway conforms.

On the shaft 63 is mounted a sprocket wheel 65 driven through acompensating mechanism, later described, and acting in turn to impartthe necessary movement to the foot board cam M. Since the radialdistance between the shaft 63 and the trackway 53 varies at differentpoints in the orbital movement of the hand, the connecting rod 59 ismounted for sliding movement in the two opposite arms of the crankmember 61 (Fig. 3), which latter is fixedly secured to the shaft 63. Theresult is that as the hand sweeps forward along the upper horizontal runof the trackway toward the downwardly extending part thereof, theconnecting rod slides outwardly in its crank arm increasing theeifective radius or leverage, and as it moves back on the horizontal runof the trackway it slides into the crank arm decreasing its effectiveradius or leverage.

The two opposite sprocket wheels 65 are connected each by a sprocketchain to drive sprocket wheels 68 fixed on opposite ends of theintermediate shaft 69, the latter journaled in bearings secured on theupright frame members 25 and 21, the shaft 69 in turn having fixedlysecured to it the larger intermediate sprocket wheel H connected by asprocket chain to drive the smaller, rear sprocket wheel 13 secured tothe foot-board cam shaft 49 for turning the foot-rest cams 41.

The two roller guide frames occupy positions at all times 180 apart withrelation to the. axis of the shaft 63. The sprocket wheels 65 and 68 areof the same size so that the shaft 69 and sprocket wheel ll make onecomplete revolution for each complete cycle of arm movement. Theintermediate sprocket wheel H is herein three times the diameter of thesprocket wheel 13, so that for each complete cycle of arm movement thecams 41 each complete three revolutions, enforcing three beats orcomplete reciprocations of each leg board or an aggregate of six beatsfor the two legs of the swimmer, the movements of the two legs beingopposite to each other and in alternation. This provides the legmovement ordinarily 5 used in the American crawl stroke, but byreplacing the intermediate sprocket wheel H or the cam shaft sprocketwheel 13 with wheels of different sizes, the number of beats for eachcycle of arm movement may be varied as desired 10 During the forwardmovement of one guiding frame, for example, the left-hand frame, on thehorizontal run of trackway, and until it reaches the arc-shaped portionthereof, the other or righthand guiding frame is traveling on thearc-shaped 15 portion and at a relatively greater linear velocity thanthe first or left-hand frame. Accordingly, the movement of theright-hand shaft 63 driven thereby tends to accelerate with relation tothe movement of the companion or left-hand driving 10 shaft. To preventthe acceleration in the movement of one shaft from interfering with thesimultaneous retardation of the movement of the other shaft, a lostmotion orcompensating driving connection (Figs. 3 and 4) is providedbetween each It" shaft and its driven sprocket wheel 65, both of which,it will be recalled, are chain-geared to the same intermediate drivingshaft 69.

For this purpose the sprocket wheel 65 is loose on the shaft 63 but isprovided with a pin 15 posltioned eccentrically andextending laterallyfrom the inside face of its hub. The pin 15 projects into a recess 11formed in the opposing face ofa collar 19 fixedly secured to the shaft63. When the shaft 63 is rotated the collar and pin serve as the drivingconnection for the sprocket wheel. The recess Tl, however, permits thepin to move therein and the shaft 63 on one side of the ma chine to lagbehind its sprocket wheel when the shaft on the opposite side isaccelerated by the 0 travel of its guiding frame over the arc-shaped.portion of the trackway.

This not only relieves any binding action in the gearing connectionbetween the two shafts 63, but automatically transfers the load ofdriving 45 the apparatus to the arm which is executing the downward,backward and upward sweep, present ing an increased resistance thereto,while relieving from any substantial load the other arm which is beingextended forwardly. This simu- 50 lates the conditions in actualswimming, where the downward and backward sweep of the arm is themovement through which propulsive power is imparted to the strokeagainst the resistance of the water, while the subsequent forward move-55 ment of the arm is merely intended to reposition the hand forrepeating the power stroke.

If desired, means may be provided additionally to impose an artificialload on the arm movement when executing the first part of the downwardand backward sweep where somewhat more resistance is encountered inperforming the. stroke in the water than in the finishing part of thesweep. As illustrative of such means. (see Figs. 6 and 7) there is shownas secured to one: OS face of the intermediate sprocket wheel H twooppositely positioned and spaced segmental brake: shoes 8|, in the pathof the periphery of which there lies a curved spring 83 adapted to.exert a frictional drag on the sprocket wheel when the 7 shoe passesthereover. The free end of the spring rests slidably in a yoke 85supported between the frame members 5|. The result is that as one arm ofthe swimmer sweeps down over the first part of the arc-shaped portion ofthe trackway, one 7 of the shoes engages with and passes over thespring, adding somewhat to the resistance encountered by the movement ofthe arm, this additional resistance being relieved during the time thearm performs its upward sweeping movement, but a similar and similarlytimed resistance being imposed on the other arm when the other segmentalshoe passes over the spring 83. It will be observed that the radialdistance from the center of the sprocket Wheel to the periphery of eachbrake shoe is greater near the middle of the shoe and decreases somewhattoward each end, the result being that the effort required to be exertedby the swimmer in the execution of the power stroke first increases andthen decreases in close simulation to the effort called for in executingthe stroke in the water.

The operation of the apparatus will be readily understood from theforegoing. To operate the machine, the swimmer lies face downward on thetable, placing each foot in the respective foot rest and placing eachhand in the hand strap provided. Adjustment may be made in each case toaccommodate the stature of the swimmer. By pushing the roller guidingframes forward and around the trackway the driving mechanism is set intooperation, causing the legs to move up and down in the desired ratio andin coordination with the movement of the arms.

This not only provides a beneficial exercise and a means for teachingthe novice the correct stroke, with perfect coordination of the movementof the legs and arms, but also a means for perfecting the stroke andkeeping in practice where swimming facilities are not available, and atthe same time develops the muscular power required for performing thestroke.

While I have herein disclosed and described for the purpose ofillustration one specific embodiment of the invention, it is to beunderstood that this is illustrative only and that extensive deviationsand changes may be made in the apparatus herein illustrated, all withinthe scope of the claims and without departing from the spirit of theinvention.

I claim:

1. In an apparatus for instructing in the crawl stroke of swimming, thecombination with means for supporting the body of the swimmer in proneposition, of means for directing the movement of the two handsalternately first forward and then downward and backward in asubstantially vertical plane, and mechanism driven by the movement ofsaid hands, said mechanism having means to present a greater resistanceto the downward movement of each hand than to the forward movementthereof.

2. In an apparatus for swimming instruction, the combination with meansfor supporting the body of the swimmer in prone position, connectionsfor attaching to the apparatus the legs and arms of the swimmer,mechanism for guiding and coordinating the movements of the arms andlegs, means for driving said mechanism through the muscular power of theswimmer, and means for imposing a different load on the swimmer fordifferent parts of the swimming stroke.

3. In an apparatus for swimming instruction, the combination with meansfor supporting the body of the swimmer in prone position, of anoncircular guiding trackway defining an orbit for each hand of theswimmer, means adapted to be secured to each hand of the swimmer forguiding said hand along said trackway, a driving member connected to berotated by the movement of each hand through said orbit, a driven memberfor each driving member, said driven member being interconnected tomaintain the hands in fixed relationship one to the other, and a lostmotion connection between each driving and driven member.

4. In an appartus for swimming instruction, the combination with meansfor supporting the body in prone position, of a non-circular guide fordirecting the movements of each hand of the swimmer in an orbital pathin alternation first forwardly and then downwardly and backwardly, adriving member connected to be driven by the movement of each hand at avarying rate of speed in different parts of the orbital path, a drivenmember, and a lost motion connection between the driving and drivenmember.

5. In an apparatus for swimming instruction, the combination with meansfor supporting the body of the swimmer in prone position, of a guide foreach hand defining a non-circular orbit, mechanism driven by the jointmovement of said hands, and a lost motion driving connection betweeneach hand and the said driving mechanism.

ERHARD HESS

